Compressor shaft assembly



March 4, 1952 M. KURTZ COMPRESSOR SHAFT ASSEMBLY Filed July 2, 1948 v 4 a 2 lII /l l Inventor. Lowell M. Kurbz, b3

His Attorngg li/IllI/IIIII II Patented Mar. 4, 1952 UNITED STATES PATENT OFFICE QQMPRESSOR SHAFT ASSEMBLY Lowell M. Kurtz, Erie, Pa., asslgnor to General Electric Company, a corporation of New York Application July 2, 1948, Serial No. 36,720

13 Claims. 1

My invention relates to compressors for refrigerating machines and the like and more particularly to shaft assemblies for such compressors.

In the manufacture of such items as compressors in large quantities the size of the various parts may vary slightly within the range of tolerances. In hermetically sealed motor compressor units the crankshaft of the compressor is carried within a frame. Manufacturing tolerances with regard to the shaft and the frame, for example, may result in a variation between different compressors in the amount of the end play of the shaft relative to the frame. Such variations might result in an undesirably large amount of end play and in a resultant unsatisfactory operation of the compressor.- Accordingly, it is an object of my invention to provide an improved arrangement for adiustment of the end play of a compressor shaft assembly.

Further objects and advanta es of my invention will become apparent as the following description proceeds and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

For a better understanding of my invention ref erenee may be made to the accompanying drawing in which Fig. 1 is an elevation view. partly in section, of a motor-compressor unit embodying my invention; Fig. 2 is an exploded view of some of the elements included in Fig. 1; Fig. 3 is a sectional view of a port on of a compressor assembly illustrating a modified form of my invention; Fig. 4 is an exp oded view of some of the elements included in Fig. 3; Fig. 5 is a sectional view of a port on of the compressor assembly shown in Fig. 3 illustrating another modified form of my invention: and Fig. 6 is an exploded view of some of the elements shown in Fig. 5.

Referring now to Figs. 1 and 2, there is shown a hermetically sealed motor-driven refrigerant compressor unit I. This unit includes a hollow generally-cylindrical shell 2 to which end plates 3 and 4 are welded or otherwise suitably bonded to form a closed casing. An electric motor 5 is arranged within one end of the shell 2. The stator 6 of the motor is held between annular rings 1 and 8, which are welded or otherwise suitably bonded to the shell 2. The rotor 9 of the motor is arranged within the stator 8. Power is supplied to the stator windings through leads Ill which pass through sealed insulating fittings II 2 sor includes a frame l2 which is rigidly secured within the casing. The compressor further includes a reciprocating piston (not shown) driven through a connecting rod H from a shaft II. The connecting rod is carried on an eccentric or crank, portion I6 of the shaft I5 so as to convert the rotary motion of the shaft to reciprocating motion of the piston.

The shaft is carried within a longitudinal bearing formed in .the frame i3, and the hub ll of the rotor 9 is secured in any suitable manner, as by a pressed fit, to the shaft l5, so that motion of the rotor is transmitted directly to the shaft.

The hub in its assembled position may be re-- garded as an integral part of the shaft and is so treated in references in the claims to the axial passage for receiving the adjustable element.

The frame I3 is formed to'provide two axially spaced thrust bearings l9 and 20. The shaft I5 is provided with a shoulder 2| which is adapted to engage the thrust bearing l9, thus limiting the axial movement of the shaft in one direction. In order to limit the axial motion of the shaft in the opposite direction an annular member or ring 22 is slidably arranged on the shaft and is adapted to engage the thrust bearing 20. As can be seen from the drawing, the end play of the shaft is determined b the distance between the shoulder 2| and the ring 22 relative to the distance between the thrust bearin s l9 and 20. In order to adjust the amount of suchv end play.

an a rangement for varying the position of the ring 22 is provided. This arrangement includes a pin or member 23. which extends through an opening 24 in the shaft, and an adjustab e ele-v ment 25, which is received within an axial passage in the shaft. The adjustable element 25 includes a rod 26 and a screw-threaded portion 21 having a recessed end 28 for receiving the rod. Although the adjustable element 25 has been shown as including the two portions 26 and 21 to facilitate alignment, it will be apparent as this specification proceeds that the adjustable element could be formed, if desired, as a unitary structure. The exposed end of the threaded portion 21 of the adjustabe element is provided with a slot 29 for engagement by a screw driver during the adjusting operation. From the drawing it can be seen that the ring 22 can be positioned closer to or farther away from the shoulder 2| as the adjustable element 25 is screwed inwardly or outwardly with respect to the shaft l5. This provides asimple arrangement for adjusting the amount of end play so that, despite any slight variations in the sizes of the various parts of the compressor 3 unit resulting from mass production manufacturing tolerances,,the amount of end play can be adjusted to any desired minimum. A look nut 33 is provided for locking the adjustable element in its adjusted position.

The various parts which make up the adjustins structure are shaped along their engaging surfaces so as to provide for self-alignment thereof. Thus the ring 32 is provided with two arcuate aligned grooves 3|, and the adjacent surface 32 of the pin 33 is correspondingly curved. The pin 23 includes a flat surface 33 which is engaged by a flat end 34 of the rod 23. By the construction outlined above any variations such as having the thrust bearing surface 23 not. exactly perpendicular to the axis of the shaft or having the adjustable element 33 somewhat out of line with the axis of the shaft are automatically compensated from an alignment standpoint by the arrangement of the elements themselves.

Referring now to Figs. 3 and 4, there is shown a modified form of my invention. I have shown the hub l3 of a rotor secured, as by a pressed fit, to the shaft ii. A portion of the frame I3 is also illustrated, including the thrust bearing 29.

In order to provide for adiustment of end play an annular member or ring 35, corresponding to the ring 22 shown in the previously described form. is slidably arranged on the shaft i 5 and is adapted to engage the thrust bearing 23. In order to position the ring 35 an adiusting structure is provided. This structure includes a second annular member or ring 33, which is adapted to engage the ring 35, and an adiustable element 31, which engages a portion of the ring 33. The adjustable element 31 is positioned within an axial passage 33 within the hub i8 and is provided with threads 33 for threaded engagement with the hub 18'. It can be seen by reference to Fig. 3 that screwing the adjustable element 31 inwardly or outwardly results in a shifting of the ring 35 to the right or left to decrease or increase the end play, in the same manner as.the adjustment described in connection with the form illustrated in Figs. 1 and 2. The adjustable element 31 is provided with a slot 43 for engagement by a screw driver in making adjustments, and a nut 4| is provided for looking the element in the adjusted position.

In order to provide for alignment of the parts the surface 42 of the ring 35 on the side adjacent the ring 33 is curved as shown in the drawing. Thus the ring 35 has its maximum thickness along one transverse axis and its minimum thickness along a transverse axis at right angles to the first mentioned axis. In order to further facilitate self-alignment the left-hand face of the ring 33 as viewed in Figure 3, that is the under surface of this ring as viewed in Figure 4, may also be curved, the curvature being indicated by the dotted line 36a in Figure 3.

- The curvature of the face of the ring 36 is arranged so that a transverse line extending through the portions of the maximum thickness of the ring 33 is displaced 90 from the transverse axis extending through the portions of maximum thickness of the ring 35. In order that the rings 35 and 33 rotate as a unit the ring 35 is provided .with a pin 43 which is adapted to fit within a recess 44 formed in the ring 33. Similarly, the ring 33 includes a pin 45 adapted to fit within a recess 43 in the ring 35. The pins and recesses are arranged along' the axis which includes the portions of maximum thickness of the ring 35. The ring 33 includes a pin 41 which fits within a recess CI in the hub ll, so that the the rotor. Although the adjustable element 31 has been illustrated as a unitary structure, it will be apparent that, if desired. this element could be formed in two parts, similar to the adjustable element 33.

Referring now to Figs. 5 and 6, there is shown another modified form of my invention which includes an alternative arrangement for effecting self-alignment. The compressor assembly structure is the same as that illustrated in Fig. 3 and the same numerals have been applied to corresponding parts.

Referring first to Fig. 5, there is illustrated a portion of the frame II. There is also shown the hub 13 of the rotor secured, as by a pressed fit, to the shaft l5. Between the thrust bearing 23 on the frame i3 and the hub i3 there are arranged two annular members or rings 43 and 43. The adjustable element 31 is arranged to bear against the ring 43' and motion of the adjustable element is transmitted through the ring 43' to the ring 43 to vary the and play of the shaft relative to the frame.

The ring 43 corresponds generally to the ring 35 shown in Fig. 3, but both faces of the ring 33 are fiat whereas one face of the ring 35 is curved, as shown at 42, to facilitate self-alignment. In order to provide for universal self-alignment, the ring 43' is provided with raised portions 56 .and 5| on opposite faces of the ring, and these portions are arranged along axes spaced 90 degrees from each other. The raised portion 53 engages the adjacent face of the ring 49 and the raised portion 5! engages the hub it. By this construction the ring 43 may pivot about axes arranged at 90 degrees relative to each other so as to compensate for misalignment.

In order to prevent relative rotation between the rings 43 and 39', the ring 33 is provided with two openings 52 along the axis of the raised'portion 53. Two pins 53 are provided on the ring 33 and are adapted to fit within the openings 52 in the assembled position of the rings so as to prevent relative rotation of the rings. Similarly, the ring 43 is provided with an opening 54 along the axis of the raised portion 5!, and a pin 5 provided in the hub i8 is adapted to fit within the opening 54 to prevent relative rotation between the rotor and the ring ee'. The adjustable element 31 is arranged to engage the ring 43' along the axis of the raised portion St at a point 180 degrees from the opening 53.

While I have shown and described specific embodiments of my invention, I do not desire my invention to be limited to the particular constructions shown and described and I intend, by the appended claims, to cover all modifications within the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In a compressor or the like, a frame including a shaft bearing, a shaft journaled in said bearing, a first thrust bearing formed on said frame, said shaft including a shoulder adapted to engage said first thrust bearing, a second thrust bearing formed on said frame and axially spaced from said first thrust bearing, a

first member arranged on said shaft and adapted and an adjustable element received in said passage for engaging said second member tovary the position of said first member, at least one of said members being curved with respect to a plane extending transversely of said shaft to means for adjusting the end play of said shaft relative to said frame, said means including a second member engaging said annular member, and an adjustable element received in said passage for engaging said second member to vary the position of said annular member, at least one of said members being curved with respect to a plane extending transversely of said shaft to facilitate self-alignment.

3. In a compressor or the like, a frame including a shaft bearing, a shaft journaled in said bearing, a first thrust bearing formed on said frame, said shaft including a shoulder adapted to engage said first thrust bearing, a second thrust bearing formed on said frame and axially spaced from said first thrust bearing, an annular member arranged on said shaft and adapted to engage said second thrust bearing, means for adjusting the end play of said shaft relative to said frame, said means including a pin extending transversely through said shaft and engaging said annular member, and an adjustable element for engaging said pin to vary the position of said annular member.

4. In a compressor or the like, a frame including a shaft bearing, a shaft journaled in said bearing, a first thrust bearing formed on said frame, said shaft including a shoulder adapted to engage said first thrust bearing, a second thrust bearing formed on said frame and axially spaced from said'first thrust bearing, a first member arranged on said shaft and adapted to engage said second thrustbearing, said shaft having an axially extending passage therein, means for adjusting the end play of said shaft relative to said frame, said means including a second member engaging said first member, an adjustable element received within said passage for engaging said second member to vary the position of said first member, at least one of said members being curved with respect to a plane extending transversely of said shaft to facilitate self-alignment, and means for looking said adjustable member in its adjusted position.

5. In a compressor or the like, a frame including a shaft bearing, a shaft journaled in said bearing, a first thrust bearing formed on said frame, said shaft including a shoulder adapted to engage said first thrust bearing; a second thrust bearing formed on said frame and axially spaced from said first thrust bearing, said shaft having an axial passage therein, a first member arranged on said shaft and adapted to engage said second thrust bearing, means for adjusting the and play of said shaft relative to said frame, said means including a second member engaging said first member, the engaging surfaces of said members being curved with respect to a plane. transversely of said shaft to facilitate self-alignment, and an adjustable element extending through said passage and in threaded engagement therewith for engaging said second member to vary the position of said first member.

6. In a compressor or the like, a frame including a shaft bearing, a shaft journaled in said bearing. a first thrust bearing formed on said frame, said shaft including a shoulder adapted to engage said firstvthrust bearing, a second thrust bearing formed on said frame and axially spaced from said first thrust bearing, said shaft having an axial passage and a transverse passage therein, a first member arranged on said shaft and adapted to engage said second thrust bearing, means for adjusting the end play of said shaft relative to said frame, said means including a second member extending through said transverse passage and engaging said first member, and a threaded element arranged within said axial passage and engaging said second ibnember to vary the position of said first mem- 7. In a compressor or the like, a frame including a shaft bearing, a first thrust bearing formed on said frame, said shaft including. shoulder adapted to engage said first thrust bearing, a second thrust bearing formed on said frame and axially spaced from said first thrust bearing, said shaft having an axial passage and a transverse passage therein, a ring arranged on said shaft and adapted to engage said second thrust bearing, said ring having a transverse groove therein, means for adjusting the end play of said shaft relative to said frame, said means including a pin extending through said transverse pa sage in said shaft and having a rounded surface adapted to within said groove, said pin including a flat surface, and an adjustable element arranged .in threaded engagement with said axial passage in said shaft for engaging the fiat surface of said pin to vary the position of said ring.

8. In a compressor or the like, a frame including a shaft bearing, a shaft journaled in said bearing, a first thrust bearing formed on said frame, said shaft including a shoulder adapted to engage said first thrust bearing, a second thrust bearing formed on said frame and axially spaced from said first thrust bearing, two rings arranged on said shaft, one of said rings being adapted to engage said second thrust bearing and at least one of said rings being curved with respect to a plane extending transversely of said shaft to facilitate self-alignment of said rings, and an adjustable element for engaging one of said rings to vary the end play of said shaft relative to said frame.

9. In a compressor or the like, a frame including a shaft bearing, a shaft journaled in said bearing, a first thrust bearing formed on said frame, said shaft including a shoulder adapted to engage said first thrust bearing, a second thrust bearing formed on said frame and axially spaced from said first thrust bearing, two rings arranged on said shaft, one of said rings being adapted to engage said second thrust bearing, at least one of said rings having a curved face to facilitate self-alignment of said rings, at least one pin arranged between adjacent faces of said rings at the point of maximum thickness of said ring having said curved face to prevent relative rotation between said rings, and an adjustable element for engaging one of said rings to vary the end plus of said shaft to said frame.

-10. In a compressor or the like, a frame including a shaft bearing, a shaft Journaled in said bearing, a first thrust bearing formed on said frame, said shaft including a shoulder adapted to engage said first thrust bearing, a second thrust bearing formed on said frame and axially spaced from said first thrust bearing, two rings arranged on said shaft, one of said rings being adapted to engage said second thrust bearing, at least one of said rings having a curved surface -to facilitate self-alignment of said rings, a pin extending between adjacent surfaces of said rings to prevent relative rotation of said rings, a second pin extending between one of said rings and said shaft to prerelative vent relative rotation between said rings and said shaft, said shaft having a longitudinal passage therein, and an adjustable element extending through said passage and engaging said last-named one of said rings at aposition substantially 180 degrees from said second pin for varying the end play of said shaft. relative to said frame.

11. In a compressor or the like, a frame including a shaft bearing, a shaft journaled in said bearing, a first thrust bearing formed on said frame, said shaft including a shoulder adapted to engage said thrust bearing, a second thrust bearing formed on said frame and axially spaced from said first thrust bearing, two rings arranged on said shaft, one of said rings being adapted to engage said second thrust bearing, each of said rings having a curved surface to facilitate self-alignment, the axes of said curved surfaces of said rings being spaced 90 degrees from each other, the adjacent faces of said rings including a plurality of cooperating pins and recesses to prevent relative rotation between said rings, said shaft including a recess and a longitudinal passage, one of said rings including a pin adapted to engage said recess in said shaft for preventing relative rotation between said one of said rings and said shaft, an adjustable element extending through said longitudinal passage in said shaft in threaded engagement therewith and engaging said one of said rings at a position substantially 180 degrees from said last-mentioned pin to vary the end play between said shaft and said frame, and means for locking said adjustable element in its adjusted position.

12. In a compressor or the like, a, frame including a shaft bearing, a shaft journaled in said bearing, a first thrust bearing formed on said frame, said shaft including a shoulder adapted to engage said first thrust bearing, a second thrust bearing formed on said frame and axiallv spaced from said first thrust bearing,

essence a first ring arranged on said shaft and adapted to engage said second thrust bearing, aeecond ring arranged on said shaft and adapted to engage said first ring, said second ring being shaped to provide raised portions on opposite faces thereof arranged along axes spaced degrees from each other to facilitate self-alignment, and an ad- Justable element for engaging said second ring at a point along one of said axes to vary the end play of said shaft relative to said frame.

18. Ina compressor or the like, a frame including a shaft bearing, a shaft Journaled in said bearing. a first thrust bearing formed on said frame, said shaft including a shoulder adapted to engage said first thrust bearing, a second thrust bearing formed on said frame and axially spaced from said first thrust bearing, a first ring arranged on said shaft and adapted to engage said second thrust bearing, a second ring arranged on said shaft and adapted to engage said first ring, said second ring being shaped to provide raised portions on opposite faces thereof arranged along axes spaced 90 degrees from each other to facilitate self-alignment, said second ring including an opening arranged at a point along one of said axes, said first ring including a pin adapted to fit within said opening to prevent'relative rotation between said rings, said second ring including a second opening arranged at a point along the other of said axes of said second ring, said shaft in-= cluding a pin adapted to engage said second opening for preventing relative rotation between said second ring and said shaft, and an adjustable element arranged in threaded engagement with said shaft and adapted to engage said second ring at a point along the same axis as said second opening for varying the end play of said shaft relative to said frame.

LOWELL M. KURTZ.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,165,655 Eldridge Dec. 28, 1915 1,272,041 Herr July 9, 1918 1,557,524 Hanson Oct. 13, 1925 1,839,497 Peterson Jan. 5, 1932 2,081,354 Drysdale May 25, 1937 2,113,451 Leland Apr. 5, 1938 2,210,731 Ritter Aug. 6, 1940 FOREIGN PATENTS Number Country Date 223,753 Great Britain Oct. 30, 192% 

